1. Field of the Invention
The present invention relates to a pattern forming method and an actinic ray-sensitive or radiation-sensitive resin composition for use in the method. More specifically, the present invention relates to a negative type pattern forming method which is suitably used for a process for manufacturing a semiconductor such as an IC, a process for manufacture of liquid crystals and a circuit board for a thermal head or the like, and a process used in other lithographic processes of photofabrication; and an actinic ray-sensitive or radiation-sensitive resin composition used in the same. In addition, the present invention further relates to a method for manufacturing an electronic device, including the pattern forming method, and an electronic device manufactured by the method.
2. Description of the Related Art
Since a resist for a KrF excimer laser (248 nm) was developed, a pattern forming method using chemical amplification has been used in order to complement desensitization caused by light absorption. For example, in a positive type chemical amplification method, first, a photoacid generator included in an exposed area decomposes upon irradiation with light and generates an acid. Thereafter, in a process such as post exposure bake (PEB), and the like, an alkali-insoluble group included in the actinic ray-sensitive or radiation-sensitive resin composition is changed to an alkali-soluble group by the catalytic action of the generated acid. Subsequently, development is carried out, using, for example, an alkali solution. Accordingly, the exposed area is removed to obtain a desired pattern.
In the above method, various alkali developers have been suggested as an alkali developer. For example, as the alkali developer, a water-based alkaline developer with 2.38% by mass of an aqueous tetramethylammonium hydroxide solution (TMAH) is universally used.
In order to make semiconductor elements finer, a wavelength of an exposure light source has been shortened and a projection lens with a high numerical aperture (high NA) has been advanced. Thus, an exposure machine using an ArF excimer laser having a wavelength of 193 nm as a light source has been currently developed. As a technique for further improving resolving power, a method (that is, a liquid immersion method) of filling a liquid having a high refractive index (hereinafter also referred to as an “immersion liquid”) between a projection lens and a sample has been proposed. In addition, EUV lithography that performs exposure with ultraviolet rays at a shorter wavelength (13.5 nm) has also been proposed.
Under these circumstances, various configurations have been proposed as a positive type resist composition. In addition, a pattern forming method using not only the current mainstream positive type but also a negative type developer, which is a developer containing an organic solvent is being developed (see, for example, JP2013-105165A and JP2008-292975A). This reflects the situation in which in the manufacture of a semiconductor element or the like, while there is a demand for the formation of a pattern with various configurations such as a line, a trench, and a hole, there exist patterns which are hardly formed with current positive type resists.